Crime Scene Investigation

Introduction:-

Most police investigations begin at the scene of a crime. The scene is simply defined as the actual site or location in which the incident took place. It is important that the first officer on the crime scene properly protect the evidence. The entire investigation hinges on that first person being able to properly identify, isolate, and secure the scene. The scene should be secured by establishing a restricted perimeter. This is done by using some type of rope or barrier. The purpose of securing the scene is to restrict access and prevent evidence destruction.

Once the scene is secured, the restrictions should include all nonessential personnel. An investigation may involve a primary scene as well as several secondary scenes at other locations. On major scenes a safe space or comfort area should be designated at the crime scene to brief investigators, store needed equipment, or as a break area.

In critical incident management the protocol that is being taught today identifies a three layer or tier perimeter. The outer perimeter is established as a border larger than the actual scene, to keep unlookers and nonessential personal safe and away from the scene, an inner perimeter allowing for a command post and comfort area just outside of the scene, and the core or scene itself. An extreme advantage will be seen by taking the time to properly teach the uniform officers and first responders to evaluate and secure the scene.

Services in this vertical are as under:-

Preserving and protecting the crime scene so that evidence can be recovered and recorded without being lost, spoilt or destroyed.

Finding out what evidence is needed, deciding the best way to recover it and collecting it as required.

Recording the scene using photography and video.

Searching for evidence footprints and for marks left by tools or weapons.

Developing, recording and capturing fingerprint evidence.

Locating, recording and recovering evidence such as fibres, blood, hair, paint or glass using various techniques.

Putting samples into protective packaging and sending them for analysis.

Keeping written records, producing statements and updating systems with details of evidence.

Bloodstain Pattern Analysis:-

Bloodstain Pattern Analysis (BPA) is the science of studying the bloody aftermath of violent crime and accidents to help investigators gather evidence.

Characterizing evidence and interpreting the results through laboratory analysis.

Reconstructing and representing events.

Preparing reports and presenting evidence in court.

Laser Scanning:-

ESR is using this new technology to record a crime scene, accurately measuring the position, size and orientation of evidence. Laser scanning can also superimpose complex evidence such as bloodstain patterns and bullet trajectories.

Footwear and Tyre Impressions:-

Our scientists can identify impressions as belonging to a shoe or tyre through matching class (pattern) and individualising (damage) characteristics present on both the impression and shoe/tyre. They are experienced at preserving and/or recording impressions and enhancing faint impressions.

Firearms and Toolmarks:-

ESR firearm investigation services include comparison of recovered projectiles and cartridges to identify the firearms that fired them; tracking of projectile trajectory; identifying residues associated with firing a firearm and estimating the distance between firearm and target. Our toolmark investigation services include comparing toolmarks at the scene with tools recovered from suspects.

Vehicle Accident Investigations:-

Our services include investigation of vehicles involved in traffic accidents. Our specialist staff can identify vehicles in a “hit and run” situation by means of paint transferred between vehicles; body filler; glass and car parts at the accident scene; fabric traces or impressions on a vehicle establishing exact place of impact. Our DNA profiling of blood and other trace evidence techniques assist driver identification; and we can provide analysis of the driver’s blood for alcohol and drugs.